The present invention relates to a clamp for gripping a long component such as a pipe or wire harness to attach the long component to a support such as a car body. The invention relates more specifically to a vibration absorbing clamp that is able to prevent transmission of vibrations between a support such as a car body and a long component such as a pipe.
Vibration absorbing clamps are used to attach a long component such as a pipe or wire harness to a support such as a car body, and to prevent transmission of vibrations between the support and the long component. In many vibration absorbing clamps, a soft plastic vibration absorbing material is arranged in a long component gripper to absorb vibrations between the gripper and the long component.
In Unexamined Japanese Patent Application Publication 9-79432 (Patent Document 1), a soft buffering plastic material is placed inside a curved wall of a pipe gripper to absorb vibration and prevent axial slippage of the pipe. When strong force is applied to the pipe axially, C-shaped edges along the curved wall of a recess in the pipe gripper and the soft buffering plastic material attached to the curved wall prevent separation of the soft plastic material.
In Unexamined Japanese Patent Application Publication 9-184580 (Patent Document 2), a vibration absorbing clamp for a pipe prevents transmission of vibration between a pipe and a support such as a car body. This vibration absorbing clamp comprises hard plastic pipe grippers for gripping pipes, and a vibration damping material disposed between a base and pipe grippers to absorb vibrations.
In Registered Japanese Utility Model 3050795 (Patent Document 3), a vibration absorbing clamp for a pipe prevents transmission of vibration between a pipe and a support such as a car body. This vibration absorbing clamp comprises hard plastic pipe grippers for gripping pipes, a hard plastic base for holding the pipe grippers and attachment to a support, and an elastomer vibration absorbing material disposed between the base and the pipe grippers to absorb vibrations between the pipes gripped by the pipe gripper and the support attached to the base.
In Unexamined Japanese Patent Application Publication 2001-343006 (Patent Document 4), a vibration absorbing clamp prevents transmission of vibration between a long component such as a pipe and a support such as a car body. This vibration absorbing clamp comprises hard plastic pipe grippers for gripping pipes, a separate hard plastic base for supporting the pipe grippers, and a vibration absorbing material disposed between the base and the pipe grippers to absorb vibrations.
The clamp in Patent Document 1 prevents separation of the soft buffering plastic material used to prevent slippage. However, the vibration absorbing function is insufficient. If the soft buffering plastic material is made thicker to improve the vibration absorbing effect, a pipe is directly gripped by the soft buffering plastic material, and the gripping strength is weakened.
The clamp in Patent Document 2 does not have a vibration absorbing material between the pipe gripper and the pipe. Thus, the gripping strength of the hard plastic pipe gripper is sufficient. The vibration absorbing effect is also better because the vibration absorbing material is disposed between the pipe gripper and the base. However, because the pipe gripper and the base are connected by a thin plate support at the bottom of the pipe gripper and the bottom of the base, vibration is transmitted via the thin plate support. The thin plate support also weakens the clamp. If the thin plate support breaks, the pipe gripped by the pipe gripper becomes detached from the base.
In the first example of the clamp in Patent Document 3, space between the pipe gripper and the base is filled with a vibration absorbing material to improve the vibration absorbing effect. However, because the pipe gripper and the base are separate components, the pipe gripper can become separated from the base. This undermines the pipe gripping function of the pipe gripper. Like the clamp in Patent Document 2, the clamp in the second example in Patent Document 3 has a base and a pipe gripper that are connected to one another by a thin plate support at the bottom of the pipe gripper and the bottom of the base. While the connection strength is better than in the first example, the vibration damping leaves room for improvement, like the clamp in Patent Document 2, and the connection strength is insufficient.
Because the clamp in Patent Document 4 has a pipe gripper and a base that are completely separate with an elastomer resin vibration absorbing material filling the space between the pipe gripper and the base, the vibration absorbing effect is high. In order to keep the base from becoming separated from the pipe gripper, a latch plate is disposed between the bottom of the pipe gripper and the bottom of the base. However, because the pipe gripper is separate from the base, sufficient force applied to the base lengthwise with respect to the pipe can cause the pipe gripper to detach from the base.